subsonic 308 load

Subsonic/Light loads
Not sure how far along you have made it but here is what I'm loading. Asked a similar question and this is what I came up with.
Lots of help on this forum

Rifle - 700 sps 20" barrel .308

Small game load

8gr Trailboss
WLR primer
Military Case
180gr lead Flat Point round nose
light crimp (found it to be slightly more accurate) *when I finally get a crony I will do some more testing.

I started at 12gr and worked down to 7gr. Found that 8gr was a little more accurate and just as quiet as 7.

Light plinking load (kids love it)

150gr CMJ-FN (Berry's bullets)
12gr trailboss
Military Case
WLR primer
no crimp

I am going to try the small game load with 220gr Round nose hornady interlocks to see it the extra weight make any difference. Will start at 12gr and work my way down.
 
The 220 gr. won't stablize in your SPS. I've tried it with a 1-10" twist and a 1-11.25" twist. It groups nicely, but the holes are oval.

How is the consistency of your load? The real test of a good subsonic load is that cold bore shots don't land several inches below the rest. You can have loads that groups nicely when the barrel is warm, but as soon as you allow it to cool, the first shot takes a dump and lands below the rest of the group.
 
Canuck44 said:
Powder doesn't explode it burns and a very light charge of pistol powder only generates so much gas and pressure when it burns. FYI My 38 S&W Webley took 2 grains of Bullseye under 150 gr bullet. Very light loading in a relatively weak action. How much lower would I have to go to blow the thing up??:rolleyes:

Take Care

Bob
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I too, have lived dangerously and played fast and loose with the rules loading for the 38 S&W. With no load data I started around 1.6 grains Titegroup with a 124 grain cast bullet IIRC. With those 360- 400 fps loads I'll never know how close to grenading my Enfield pistol I came.....:p
 
kombayotch said:
The 220 gr. won't stablize in your SPS. I've tried it with a 1-10" twist and a 1-11.25" twist. It groups nicely, but the holes are oval.

How is the consistency of your load? The real test of a good subsonic load is that cold bore shots don't land several inches below the rest. You can have loads that groups nicely when the barrel is warm, but as soon as you allow it to cool, the first shot takes a dump and lands below the rest of the group.
Click to expand...

Haven’t' noticed a problem with consistency out of a cold barrel, but I have missed a few partrige heads. When testing I only fire 5 shots then I clean and cool the barrel for 10-15 minutes. My small game load is only for short distances (under 15yrd most times).
The 220gr loads are they subsonic loads? Was reading an article/post that suggested heavier round nose bullets would stabilize easier at lower velocity, that's why I'm trying the 220.
 
Since my barrels are all over 22", the 200 gr. Lapua subsonic bullet worked best. Otherwise, anything 180 gr. and under did fine. But, I needed to lube the bore and each bullet lightly with oil in order to get consistency and avoid the cold bore dump. Regular 208/210 gr. and heavier bullets did very well with IMR SR 4759. Consistent velocities, no drop, superb groups BUT oval holes...
 
saskgunowner101 said:
I too, have lived dangerously and played fast and loose with the rules loading for the 38 S&W. With no load data I started around 1.6 grains Titegroup with a 124 grain cast bullet IIRC. With those 360- 400 fps loads I'll never know how close to grenading my Enfield pistol I came.....:p
Click to expand...

Had you loaded that round with 1.5gr you would have been typing that reply with your elbows.:D

Take Care

Bob
 
Checkout using IMR Trailboss for powder....it's big-fluffy-volume is ideally suited to this type of load development.

As usual, charge weight will depend greatly on bullet weight, but also barrel length becomes much more of a variable. I would suggest starting with heavier bullets and shorter barrels....

Brobee
 
Funny thing about Trailboss is that Hodgdon doesn't recommend it for subsonics. They list subsonic loads with Titegroup and Clays, but not with Trailboss. I called them once and asked them why that was and the guy wouldn't say exactly, he would just say that they saw something they didn't like. Don't know, lots of guys using it for subsonics without issues. I compared it to Titegroup and found Titegroups works better, and it dispensed well on a progressive press.

Five 5-shot groups with each using 180gr. RN and the oil rub trick:

P1040492.jpg

10.2 gr. Trailboss, dispensed from Chargemaster

P1040493.jpg

8.1 gr. Titegroup thrown form polished Dillon powder drop.


P.S. load your subsonics to 1000-1020 fps. if you want them to stay subsonic in cold weather...
 
Oh boy, this has gone on, hasn't it? I appreciate all the posts giving the data for loads that are "subsonic" and "plinking". Good stuff. Thanks to all posters.

I have not done much loading of "reduced" loads, i.e. using slower burning rifle powders. In fact, it would likely be 20 years or more since I've even entertained the idea. Any "reduced" load data always seemed to call for powder I didn't have. When I first started reloading, IMR 3031 was good enough for me and my 30-30's. As I acquired more guns, it followed that I gathered more different brands and types of powders. I was not into experimenting. I pretty much followed the load data in my two or three manuals. I only started loading "plinking loads", like the ones I mentioned earlier, after I read an article somewhere about this type of load.

Since then, I haven't done any experimenting either. I have fired thousands of "light loads" using 700X and sometimes Unique. Simple as that. Further, I used a Lee dipper - YES! a Lee dipper!!:eek: to charge the brass. Of course, I am now only able to type with my nose....:p

All sarcasm, cynicism, childish pouting and taking my ball home aside, I do believe it is useful to air our thoughts in these forums. Although I came to reloading with a part can of IMR 3031, a couple hundred primers and a few bullets that were included with a classic Lee Loader, I have managed to stay on the high side of any bad stuff. More luck than brains......:p

Lastly, I want everybody to know that I am a way, way younger than H4831. Way younger.......:D
 
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